A Hyundai Oilbank gas station is seen in Seoul, March 29, 2012. Reuters

By Jung Min-ho

S-Oil CEO Othman al-Ghamdi

Two South Korean energy companies have agreed to plead guilty and pay $127 million in criminal and civil fines for fixing fuel prices for U.S. military bases here.

S-Oil, whose top shareholder is Saudi Aramco, and Hyundai Oilbank will pay $75 million in criminal fines and $52 million in separate civil resolutions for rigging bids to supply fuel to U.S. Army, Navy, Marine Corps and Air Force bases, the U.S. Department of Justice said in a statement Wednesday (local time).

The Justice Department also unsealed indictments against seven South Korean nationals, including former employees of the companies, in connection with the case.

Hyundai Oilbank CEO Kang Dal-ho

"Illegal bid-rigging schemes violate fundamental tenets of government contracting and lead to inflated charges and costs to the government," said Assistant Attorney General Jody Hunt for the Department of Justice's Civil Division.

"We will not waver in our dedication to prosecuting corporations and individuals, wherever they are located, that seek to profit at the expense of American taxpayers … The department remains steadfast in its commitment to upholding the rule of law and protecting our nation's military and the American taxpayer from conduct that undercuts competition."

The Justice Department said the investigation began as a result of a tip telephoned into the Defense Logistics Agency Inspector General Hotline. The office developed the information, interviewed the complainant, and then referred the case to the investigation department.

Eric Havian, a partner at Constantin Cannon, which represents the whistleblower in the case, said his client was "an essential part of revealing this massive conspiracy to cheat consumers, the government and American taxpayers.

"This settlement is a stark example of how whistleblowers can expose back-room collusion and help bring anticompetitive behavior to justice.